This invention is directed to an electronic trigger assembly for a fuel dispensing nozzle, and, in particular, to an electronic trigger assembly that includes electronic means for sensing pressure or fluid level in order to terminate fuel dispensation when the fluid level or pressure in the fuel tank reaches a predetermined value, and for terminating fuel dispensation when the trigger assembly is not at the appropriate angle for fuel dispensation.
The promulgation of government regulations regarding fuel vapor recovery, intrinsic safeness of electronic devices used in fuel dispensation and other regulations surrounding the fuel dispensation industry have caused modifications in fuel dispensing. In particular, many attempts have been made to develop electronic devices for use in fuel dispensing systems. None of these devices have heretofore been commercialized. This is due in part to the fact that the devices do not provide substantial advancement over prior art purely mechanical devices, and these devices require separate batteries with a finite energy supply to be periodically installed within the nozzle assembly.
Prior U.S. Pat. No. 5,267,592 issued on Dec. 4, 1993 and U.S. patent application Ser. No. 161,679 filed on Dec. 2, 1993 are directed to devices for transmitting intrinsically safe electric power from the fuel dispenser through the dispensing hose to the nozzle assembly. The inventions embodied in the above-noted patent and patent application make the invention of the present application possible and are hereby incorporated by reference.
Although electronic devices used in fuel dispensing nozzles have been suggested, none of the fuel dispensing systems heretofore known includes electronic pressure sensors or mercury switches that can electronically enable and disenable the flow of fluid through the dispensing nozzle. Furthermore, this allows the enabling switches to be aligned in series, such that if either switch is disenabled, the fuel dispensing function of the nozzle is inhibited.